Flaskless molding machines are known as disclosed in such as Japanese Patent Early-Publication No. 7-16705, filed Jul. 2, 1993, assigned to the present applicant. The flaskless molding machines employ a flaskless molding process, where a molded mold is removed from a pair of flasks (an upper flask and a lower flask), and its sides are covered by mold jackets, if needed, such that it is then poured.
In the conventional flasks of the molding machine, as shown in the above publication, the paired upper and lower flasks are cantilevered supported such that they are connected to each other at just one of their sides. For this reason, an undesirable gap can appear between the upper flask and the lower flask at the side that is opposed to the connecting side when they are caused to overlap, while a gap can appear therebetween at the connecting side when a pattern is drawn. This results in that the face of the mold cannot be disposed in parallel with the mating face of the flask, and thus this causes a mold shift. The mold shift prevents the mold from being vertically drawn from a pattern and thus causes problems such as a mold dropping.
Although the upper flask and the lower flask with a mold therein overlap by especially using any aligning device for the mold, indeed, accuracy for the overlapping can be difficult to achieve.